Method of recovering metals



(No Model.)

v J. MILLER. 7

METHOD OF REUOVERING METALS.

Patentd Dec. 18, 1883.

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UNITED STATES PATENT OFFICE.

JONATHAN MILLER, or CONCORD, NEW HAMPSHIRE.

METHOD OF RECOVERING METALS.

SPECIFICATION forming part of Letters Patent No. 290,458, dated December 18, 1883, I Application filed September 6, 1883. (N0 model.)

To all whom it may concern:

Be it known that I, JONATHAN MILLER, of Concord, in the county of Merrimac and State of New Hampshire, have invented a newand Improved Method for Recovering 'the Precious Metals from their Ores; and I hereby declare the following to be a full, clear, and

exact description thereof, reference being had In the said drawing, A is a sluice leading from a stamp-mill, concentrator, or other device, through which passes off the water and unrecovered metal. I have found that the unrecovered metal escaping through such sluiices,

in the practice of the best known methods of recovery, amounts to a large percentage of the value of the ore, and thisl'save by my improved method. The sluiceA empties into a tank, B, the forward end of which is contracted to a semi-cone, a a, and has at the upper edge, in the apex of the cone, a flexible pipe, 11, which connects with the ingress -pipe (1 of a forcepump, G, made in the usual manner.

The exit-pipe e of the force-pump enters the top of a tightly-closed vessel or press, D, constructed as follows: The outer portion or shell, 2 of press D is perforated, as seen at '13. with holes of any desired dimension to enable the water to escape rapidly, and yet not weaken it sufficiently to prevent it from successfully sustaining the pressure within the press D.

Lying against the inner surface of Z is a screen of fine wire, it, which allows a free flow of water through it, and by its necessarily irregular surface so sustains an interior filter,

Z, is made of some heavy woven fabric formed into a bag, made to conform to the interior di- 'mension of the press, and is sustained by its open end being secured along its edge between flange m on the upper edge of the shell Z and the flange n on the lower edge of the cover 0 of the press. Any suitable packing may be introduced between the flanges m n to make the press air-tight.

The operation is as follows: As the products from the mill or concentrator flow from sluice A into tank B the heavy gangue falls to the bottom of the tank, while the water containing the floating material passes in a gentle current through pipe I) to the force-pump 0. Through the medium of force-pump Gthis water is passed under heavy pressure into the press D, where the clear water escapes through woven filter Z, wire-cloth k, and the holes 1 in the shell, while all the slimes and metal-bearing material are arrested by the filter Zand remain upon its inner surface. After a given quantity has been deposited, the bags are removed from the presses and dried, together with the filtrate. When dried the recovered slimes are ready to be treated by the smelter after the manner of concentrates.

I am aware that it is not new, broadly, to recover solid matters from liquid mixtures and solutions by precipitation and filtration of the supernatant liquor.

I am also aware that it is not new to accelerate the filtration of chemical precipitates by pressure induced by a barometric column applied beneath the filter to create a vacuum.

The apparatus .herein shown and described is made the subject-matter of a separate ap plication, filed November 30, 1883.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

The improved method herein described for recovering metallic particles, slimes, and similar material containing metal from liquids, consisting, essentially, in conducting the liquid and metal-bearing material to a settling-tank, allowing the gangue to fall to the bottom, drawing off the liquid, and forcing it under hydrostatic pressure through a filter-press, D, and removing and drying the filtrate, as set forth.

JONATHAN MILLER. lVitnesses:

J NO. E. THOMPSON, W. E. OHAFFEE. 

